The current health care system fails to meet the needs of most chronically ill older adults. Given that the chronically ill are the major consumers of health care dollars, development of systems that provide support in the management of the complex health care needs is critical. Care coordination is one intervention that is recognized as a mechanism to support chronically ill persons in managing their health care. However, care coordination has multiple definitions, models, providers, and settings. Most care coordination programs have been focused on specific time periods such as transition between care settings. Further, there is limited evidence about the key components of care coordination, making the content of care coordination virtually a "black box" although payment for care coordination is included in current health care legislation. Accordingly, the purpose of this proposed study is to examine the type and amount of nurse care coordination interventions and the relationship of these interventions to both patient characteristics and outcomes. To be specific, this study aims to " identify interventions used in nurse care coordination for frail older community dwelling adults; " identify the relationships among patient characteristics, components of nurse care coordination intervention, and patient outcomes;and " develop and validate models predicting patient outcomes for frail older community dwelling adults who received nurse care coordination interventions. This proposed study employs a secondary analysis that will examine existing datasets derived from a recent randomized controlled trial that tested the effectiveness of a home care medication management program (HCMM) for frail older adults. The datasets examined will include electronic patient records and communication logs documented through the CareFacts(R) system, HCMM Access database, and Medicare claims data. Due to the complexity of datasets with structured data and unstructured narrative text data, both natural language processing and statistical analyses will be employed according to the purpose of the study. This project is innovative in that it explores nurse care coordination interventions that followed patients across multiple settings with the focus on management of their chronic illness care in their day to day life over a one year period in the home setting. The results of this study will add new insight to the relationships among specific patient characteristics, care coordination interventions, and patient outcomes. This new knowledge will assist decision-making of clinicians, health administrators, and policy makers with respect to health care quality, resource utilization, cost reduction, and reimbursement policy. Also, the resulting predictive model will assist in clinical information system design to support clinicians'decision-making. PUBLIC HEALTH RELEVANCE: This proposed study will use existing data to examine the type and amount of nurse care coordination interventions provided to frail older community dwelling adults. The results of this study will add new insight to the relationships among specific patient characteristics, nurse care coordination interventions, and patient outcomes. This new knowledge also will assist decision-making of clinicians, health administrators, and policy makers with respect to health care quality, resource utilization, cost reduction, and reimbursement policy. Finally, findings can be used to inform health care consumers about nurse care coordination for frail older adults living in the community.